Unlike Office 2010, Office 2013 does not work with Windows XP or Windows Vista. Yet the latest data from NetApplications shows that roughly 45 percent of all Internet users still rock those two aging operating systems. If you're part of thatA sizableA horde, there's absolutely no reason to buy Office 2013--it won't work on your system. And because an Office 365 Home Premium subscription simply lets you install the latest version of Office--Office 2013, again--on up to five PCs, you'll want to pass on that as well.

2. Other computers may not run Office on Demand.

One of the big draws of an Office 365 subscription is Office on Demand, a full-fledged, Internet-streamed version of the productivity suite that Microsoft calls "Your Office away from home." And it really, truly is--if the host computer meets the suite's fairly stringent requirements. As with local installations of Office 2013, Office on Demand plays nice only with PCs running Windows 7 or 8. It also requires the PC to have a fairly modern browser: Internet Explorer 9 or later, Mozilla Firefox 12 or later, Apple Safari 5 or later, or Google Chrome 18 or later.

You won't be using Office on Demand at the library, in other words. (Is there a law that says all library computers have to run Windows XP?) Nor will you be using it on a Mac. While Office 365 supports installations of Office 2011 on OS X, it does not support Office on Demand for OS X.

3. Got Google? Then you got problems.

Back-and-forth sniping from Microsoft and Google isn't anything new--Scroogled, anyone?--but the spat turned especially nasty for Office 2013 adoptees a couple of months back when Google announced that it was dropping Sync support for personal users. Sync is Google's implementation of Microsoft's Exchange ActiveSync protocol. Without it, you can't natively sync your Google Calendar or Contacts to the Outlook 2013 mail client, as Outlook 2013 doesn't support the CalDAV and CardDAV protocols that free Google users must now rely upon.

Look on the bright side: You can still sync Gmail to Outlook 2013 using IMAP. Google does offer EAS/Sync support for premium, paid-for Google Apps users, but even that doesn't work with Outlook 2013, and, in any case, it bumps up against the next gotcha ...

4. Office 365 Home Premium: Small businesses need not apply.

Office 365 Home Premium sounds like a killer deal for SMBs. It offers the latest Office software--including Outlook, Publisher, and Access--on up to five computers, along with 20GB of SkyDrive cloud storage and 60 monthly Skype minutes, all for less than $10 per month. Where do I sign?

You don't. The licenses for Office 365 Home Premium and Office 2013 Home & Student prohibit using the software for commercial purposes. Currently, a small-business owner's only option is to buy pricey per-PC licenses for either Office Home & Business 2013 ($220; includes the core programs plus Outlook) or Office Professional 2013 ($400; adds Access and Publisher). Neither of those includes Office on Demand, or the Skype and SkyDrive benefits. Don't despair, though: Microsoft plans to launch Office 365 Small Business Premium on February 27, at a cost of $150 per user per year.

One alleged gotcha to ignore completely

Microsoft's marketing department needs to step up its game. After casting users into chaos with the confusing mix of capabilities in Windows RT and Windows 8, fear, uncertainty, and doubt are once again in full swing with Office 365 thanks to some mixed messages from Redmond.

Yes, between Skype, Office on Demand, and SkyDrive storage enabled by default, Office 365 definitely has its head in the cloud--but its feet are firmly planted on the desktop. To wit:A The Office apps you install as part of an Office 365 subscription do not need an active Internet connection to work. I've seen a lot of people making statements to the contrary, but it's simply not true. While the streaming Office on Demand service requires a Web connection, the five Office 2013 installations you're allowed with your 365 subscription are each fully functioning local installations and they work just fine online or offline--as long as your account as in good standing, that is.

This story, "Why Office 365 and Office 2013 may not be right for you" was originally published by
PCWorld.